Botox is temporary but inexpensive.
Although.... is it normal armpit smell? I'm surpised it could smell bad moments after getting out of the shower, having washed with soap and hot water, and using antiperspirant, becaue the "stale armpit smell" is the dead bacteria, I though, rather than the smell of fresh sweat, which generally smells quite nice.
Do you use strong antiperspirant (Mitchum or similar) or something "natural"?
So I wonder if it's connected to something else?
A quick google suggested:
"Diabetes.
Gout.
Menopause
Overactive thyroid.
Liver disease.
Kidney disease.
Infectious diseases.
If you have diabetes, a change in body odor could be a sign of diabetic ketoacidosis."
Or:
"Sulfur smells like rotten eggs. When it’s secreted from your body in your sweat, it can put off an unpleasant smell. Examples of sulfur-rich foods are:
Onions.
Garlic.
Cabbage.
Broccoli.
Cauliflower.
Red meat."
my.clevelandclinic.org/health/symptoms/17865-body-odor
It seems lazy of your doctor to dismiss it. A sudden change in your body chemistry happens for a reason.